Thread rolling and machining apparatus



Nov. 1, 1966 E- A. TAYLOR THREAD ROLLING AND MACHINING APPARATUS 4 Sheets-Sheet 1 Filed Oct. 17, 1963 INVENTOR.

ATTOR/ViVS Nov. 1, 1966 A. TAYLOR THREAD ROLLING AND MACHINING APPARATUS 4 Sheets-Sheet 2 Filed Oct. 1'7, 1963 m M M r r A BY? [if 1 Nov. 1, W66

E- A. TAYLOR 3,282,,U8Q

THREAD ROLLING AND MACHINING APPARATUS Filed Oct. 17, 1963 4 Sheets-Sheet 5 INVENTOR fdV/A/ 4. 734)! H956 E. A. TAYLOR THREAD ROLLING AND MACHINING APPARATUS 4 Sheets-Sheet 4 Filed Oct. 17, 1963 Flmxl llll I I llOlj Mo/EIIAI INVENTOR.

ATTORAQFVS United States Patent The present invention relates to improved equipment for the rolling of a precision part to provide a thread thereon, the thread rolling being accompanied by a concurrent turning or machining of the part, as by facing and/ or chamfering, to provide a machined surface which is very accurately located with respect to the threading. An example of a part requiring such precision location of machined surfaces to a thread helix is in the differential adjuster of an automotive differential bearing; however, various other components may well be produced by combined thread rolling and metal removing equipment such as the invention alfords. A

More particularly, the invention relates to an improved attachment for association with a known type of automatic thread rolling machine, whereby the latter may, at minimum expense and difiiculty, be converted for the combined thread rolling and metal removing, operations referred to above.

While different types of thread rolling machines are well-known and available to the trade, the invention contemplates the application of such attachment to a type of machine such as is produced by the Reed Rolled Thread Company of Worcester, Massachusetts, the patent to Plagemann No. 2,422,849 of June 24, 1947 being illustrative in a general way of the type in question. It employs a set of three driven thread forming rolls which are driven on parallel axes equally spaced circumferentially from one another. Such rolls are operated under fluid pressure control for their radial movement into and out of rolling engagement with a workpiece or part; however, such rolls as embodied in the rolling machine proper may be, and are commonly, operated mechanically for their radial in and out movements, and the attachment of the present invention is in fact illustrated in association with such a mechanically operated thread forming set.

In particular, the attachment derives its drive from known means by which the conventional threading rolls are operated, both as to radial action and rotation; and a significant feature of the invention involves such a correlated drive in which the timing of the operation of the facing and/ or chamfering means of the equipment causes its machining engagement with the workpiece or part only after the thread roller has formed a substantial portion of an external helical thread on the part. This insures the desired positional accuracy of the machined surface or surfaces relative to the parts threading.

It is an object of the invention to provide attachment equipment of the sort described to supplement the action of a known type of thread rolling machine, thereby adapting the same for additional combined work, such as top facing or edge chamfering, which attachment is readily and inexpensively mounted, by means of a simple superstructure, to a standard thread rolling machine.

A further object is to provide equipment of this sort in which facing, chamfering and/ or other machine tool heads of the equipment approach an upright workpiece Patented Nov. 1, 1966 between the thread rolls in paths inclined radially inwardly and downwardly of the workpiece or part, which is suitably clamped and supported for rotation under thread rolling action. The paths of radial action of the heads are also offset angularly somewhat from those of the rolls, as the latter engage the part.

Thus engagement with the part by such head or heads is had, without interference from above and to a side of the threading rolls; and it is in turn readily possible to keep the work area clear of chips or shavings produced in the facing, chamfering and/or other turning operation.

In accordance with the invention, the machining heads in question are reciprocated in their angularly inward and downward convergent paths by fluid pressure operated devices, which are in turn controlled by individual valve means so as to occasion their operation in predetermined timed relation to threading engagement of a workpiece or part by the thread forming roll set. Such valve means are operated under the timing control of a rotative cam assembly which is driven directly from the drive and control means of the thread rolling machine.

As indicated above, the arrangement is such that the turning or machining heads are located in angularly spaced relation to one another about the rotative axis of the work part, and are timed to take initial machining engagement with the part only after a substantial portion of a thread has been formed thereon by the thread forming roll set, with the part accurately located and clamped from above and below to insure the upright trueness of its axis while being threaded. Thus it is made sure that, with the workpiece already firmly engaged and partially threaded, the faced, chamfered or other machined surfaces will be formed thereon in a needed, very accurately predetermined positional relationship to the threading.

Another object is to provide equipment for the simultaneously concurrent threading and machining of a part, which equipment includes means for the above-mentioned accurate locating and clamping of the part for rotation on a vertical axis under the driving action of the threading roll set. Such locating and clamping means includes a vertically depressible work support and elevator unit, supported, from beneath on a top plate of the thread rolling machine, and a vertically acting work locating and clamping unit coacting with the first named unit in the mentioned function. The work locating and clamping unit is supported from above the working area by the superstructure applied to a rolling machine as a support for the charnferingand facing heads.

A still further object of the invention is to provide attachment-type equipment of the kind mentioned in the preceding paragraph which, in addition to the mentioned provisions for locating and clamping the part for rotation about a true vertical axis in being threaded, also includes auxiliary work part locating means of an improved nature. Such means is positioned to a side of the axis of rotation for engagement with a part to be worked, upon advancement of the part into position above the vertically depressible work support and elevator unit. The auxiliary means includes a shaped gauge engaged by the thus advanced part at the time that the facing and chamfering heads are withdrawn, and while the upper work locating and clamping unit is in an upwardly withdrawn position, thus enabling the part to be laterally positioned accurately for subsequent engagement by the last named unit upon its downward work clamping stroke.

The auxiliary work locating device is, like the machining heads in their inward and outward radial strokes,

- operated by pneumatic means, such pneumatic operator for the auxiliary locator being accurately timed in relation to the operators for the machining heads, to be elevated above its operative initial position as the thread rolling and surface turning operations progress and end. Thus, the objective of having an open and fully accessible work area after finishing of the workpiece is supplemented, and it is readily possible to keep the work area free of chips or shavings.

Yet another specific object is to provide the above kind of equipment, in which fluid pressure devices are provided to radially operate chamfering, facing or like machining heads, under the control of cam actuated valve means, and in which such head operating devices are further equipped with hydraulic brake components to cushion the operation thereof at the end of a stroke.

Generally considered, the invention relates, in addition to attachment type equipment as referred to above, to the combination with a conventional sort of thread rolling machine characterized by a set of three rotatably driven, radial acting thread forming rolls, of such auxiliary equipment driven in timed relation to the radial action of said rolls for a material-removing machining of a part coincident with the threading of the latter.

In the equipment or combination mentioned in the preceding paragraph, the invention also contemplates specific improvements in means for supporting, clamping and guiding the workpiece as it is engaged and operated upon by the thread forming roll set and machining units. Such means takes the form of an elevator unit mounted upon the frame of the threading machine eoaxially beneath the zone of operation of the thread roll set with the rotatable cap sustained by a bearing atop an upwardly spring biased plunger of the elevator unit, so that, as engaged from above by suitable workpiece locating and clamping means, a workpiece supported by the elevator plunger cap will be depressed against the spring bias on the plunger to said zone of operation of the roll set. More specifically, the rotary plunger cap is provided with an annular shroud to shield the cap bearing and associated parts from possible damage by chips or shavings.

The workpiece locating, clamping and guiding means further comprises a part locating and clamping unit supported on the superstructure coaxially above the elevator unit, the locating and clamping unit providing a locating and clamping foot accurately formed for registering engagement with the workpiece to insure positioning of the latter truly coaxial of the elevator unit. Such foot is also anti-friction bearing mounted for rotation relative to a vertically acting plunger, downward movement of said plunger causing the workpiece to be depressed to the working zone of the threading roll set, as mentioned in the preceding paragraph. In accordance with the invention, the last named plunger is operated by a fluid pressure means which is timed in the same manner as the facing and/or chamfering means for coordinate action therewith, all of the timing control means deriving power for their operation from the thread rolling machine proper.

The foregoing as well as other objects will become more apparent as this description proceeds, especially when considered in connection with the accompanying drawings illustrating the invention, wherein:

FIG. 1 is a fragmentary top plan view, quite schematic in nature, showing basic components of the present equipment as they are adapted to be mounted by a simple superstructure on a conventional thread rolling machine of the sort referred to above, certain other provisions of that machine, including oscillatory scroll means and a thread rolling set, being indicated in dot-dash line;

FIG. 2 is a fragmentary View, partially broken away and in vertical section along the 90 broken section line A 2-2 of FIG. 1, the threading rolls (dot-dash line) and the facing and chamfering devices or units being illustrated in operative engagement with the workpiece or part;

FIG. 3 is a fragmentary view in enlarged scale and in vertical diametral cross section through a bottom work supporting and elevator unit and a part of an upper coacting work locating and clamping unit, with a workpiece or part shown accurately located and clamped between these units;

FIG. 4 is a plan view of a typical part to be threaded and machined, such as the differential adjuster for an automotive differential bearing;

FIG. 5 is a schematic top plan view, part broken, of a vertically journaled, rotative cam set and certain pneumatic valve control units governing the timed operation of the chamfering, facing, work locating and clamping, and auxiliary work gauge units or devices of the attachment; and

FIG. 6 is 'a side elevational view of the structure of PEG. 5, also indicating in dot-dash line a rotatable master control cam of the thread rolling machine, with which cam the mentioned cam set rotates to govern the action of the mentioned units of the equipment, thus timing said units accurately with the action of the thread forming roll set.

The attachment of the invention is generally designated by the reference numeral 10, and this attachment receives its support from a rigid superstructure 12 (FIGS. 1 and 2) having suitable means for mounting the same fixedly atop the frame structure of a conventional thread rolling machine of the type identified above. Since this machine is well known and readily available, its structural features and operations will not be described in great detail, nor are they illustrated other than in a general way in regard to certain basic parts to which the operation of attachment 10 is directly related.

These components include a set of three thread forming rolls 14 equally spaced circumferentially from one another in a common horizontal plane and adapted to be moved into and out of rolling engagement with a workpiece or part P (hereinafter described) in a generally radial direction relative to a rotative axis of the latter. The rolls 14 are rotatably driven about their vertical axes by suitable gear train means (not shown), and their in and out movement in radial paths derives in part from the control action of a three-lobed oscillatory scroll 16 (FIG. 1), which is a part of the thread rolling machine located beneath the set of rolls 14 and coaxial with a theoretical upright line to which the rolls converge for threading engagement with the part P. This line is therefore the rotative axis of the workpiece, as driven when worked by the roll set 14.

The source of power for the thread rolling machine is a suitably geared-down prime motor (not shown), from which the rotative drive for the threading forming rolls 14 derives, as does that of a main control cam 18 of the thread rolling machine (FIG. 6). Cam 18 is mounted on an upright axis and is operatively connected to the scroll 16 for the oscillatory drive of the latter. A set of cams, hereinafter described, is mounted coaxially of and rotates with the main or master cam 18 for the operation of certain air pressure control valves, also to be described.

Generally considered, a conventional drive for the scroll 16, such drive being shown, like the scroll, in dotdash line in FIG. 1, may comprise an arm 19 pivotally mounted at one end on a suitable part of the rolling machine framework and operatively connected by means of a connecting rod 19' pivoted on its opposite end, the rod 19' being in turn pivotally connected to a drive ring 20 fixed to scroll 16 for coaxial rotation with the latter. Arm 19 carries a follower roller 21 riding the side surface of master cam 18, being held against the latter by means of a spring unit 21, which is pivoted to a medial part of oscillatory arm 19 and, at its opposite end, to the machine frame. Thus, as master cam 18 oscillates arm 19, the latter will, through connecting rod 19', correspondingly oscillate scroll 16.

Each of the thread forming rolls 14 has its shaft pivotally mounted on the inner end of a reaction or control arm 23, which is in turn pivotally mounted at 23 to a suitable fixed part of the machine frame. Each thread forming roll 14 also has its shaft pivotally received in a second or actuating arm 25, which arm 25 in turn has its outer end pivotally connected at 25 to the scroll 16.

Thus it is seen that the arms 23 and 25, the former having a fixed pivot in space and the latter having a pivot on the scroll 16, constitute a toggle which, when the scroll 16 is moved counterclockwise (FIG. 1), causes the forming roll 14 to be advanced inwardly for rolling engagement with the workpiece P. When the scroll motion is clockwise, the toggle moves toward straightened condition, and the roll 14 is withdrawn to a retracted position for the removal of the rolled part P and the insertion of another for rolling.

The individual thread forming rolls 14 are positively driven about their respective axes by a conventional gear arrangement, to illustrate which would unduly obscure FIG. 1.

As indicated above, the operation of various components of the present equipment is under fluid pressure cona whole is operatively connected to the thread rolling trol and actuation; and the attachment equipment 10 as machine, proper, for a work cycle accurately timed in relation to the radial action of the forming rolls 14, through the agency of a rotary cam unit or set shown in FIGS. 5 and 6, the set being generally designated 22 and hereinafter referred to. The cam set, as mounted to rotate on an upright axis, operates control control valve means for the equipment 10, and obtains a positive rotary drive at speed equal to that of master threading machine cam 18, in being drivingly connected at 24 to said cam coaxially above the latter.

The cam unit 22 is rotatively iournaled in a part 26 of superstructure 12 fixedly mounted on the frame of the thread rolling machine, in a way to support the set 22 on a vertical axis which is laterally oifset substantially from the axis of rotation of the workpiece P, as the latter is rotated under rolling engagement by rolls 14. The piece is accurately supported for such rotation by work elevating, locating and clamping means to be described. The superstructure part 26 also serves as a fixed support for certain timing valve means, generally designated 28 and hereinafter described, which are timedly actuated by the cam set.

FIGS. 3 and 4 best show the workpiece or. part P in completed form. It includes an annular body flange 30 surrounding a circular center opening 31 of substantial size, the flange 30 being provided with a circumferential series of equally spaced apertures 32 on centers paralleling that of the central opening 31. The bottom of flange 30 is laterally outwardly milled at 33 to communicate the apertures 32 with the circumference of the part P.

Under the action of the thread forming set 14, an upright annular wall 34 of the part is provided with an external helical thread 35; and in the case of the particular differential part P in question it is important that the upper edge of wall 34 be provided with a smooth, truly faced surface 36, as Well as a chamfered annular edge 37. Both the surface 36 and the edge 37 must be very accurately located in relation to the threading 35 and the axis of part P. Such precision is obtained by the operation of the improved equipment conjointly and simultaneously with that of the set of thread forming rolls 14, as indicated above and as will be further described in detail.

It will of course be apparent to those skilled in the art that other pieces requiring a correspondingly accurate relationship of rolled thread and machined surface or surfaces may also be formed by equipment such as that of this invention.

As indicated above, it is essential to the purpose that the workpiece P be accurately located and held for rotation about a vertical axis under the rotative drive of the threading rolls 14. To this end, work locating and clamping means such as are shown in FIGS. 2 and 3 are employed, including a lower, resiliently upwardly biased work supporting elevator unit, generally designated 40, and an upper work locating and clamping unit 42 which coacts with the unit 40, permitting a true and free rotation of the part on its upright axis.

Thus, specially referring to FIG. 3, the elevator unit 40 comprises an upright post 43 adapted to be rigidly bolted through the agency of a welded base 44 to a horizontal plate or like structure (not shown) of the frame of the thread rolling machine. For this purpose the base 44 has three flanged ears 45, each provided with a bolt receiving hole 46.

Post 43 isupwardly flanged at 47 to fixedly receive a hollow cylindrical, upright column 48 of substantial height bolted thereto, within which column a cylindrical cup-like plunger 49 slides vertically, being urged upwardly by a coil compression spring 50. The plunger 49 preferably has an anti-rotative guide connection to column 48, as through the agency of an internal key or keys 51 of the column. However, as supported yieldingly by the plunger 49 through the provisions to be described, the workpiece P is capable of free rotation about the plunger axis.

A headed stud 52 extending through a bottom aperture 53 of plunger 49 and threaded from above into the post 43 serves to limit upward spring biased movement of the plunger. The range of vertical floating action in operation of plunger 49 is represented by the distance d (FIG. 3) between the head of the stud 52 and the top of plunger aperture 53. FIG. 3 shows the work elevator plunger 49 in its normal depressed condition, as the workpiece P is clamped downwardly against unit 40 by the coacting unit 42.

The top of hollow plunger 49 is closed by a generally cylindrical plug 55 bolted thereto; and this plug supports the lower race of a ball bearing 56. A rotating elevator head piece or cap 57 of inverted annular cup-like cross section is rotatably supported by the bearing 56, whose upper race 58 extends into and is fixedly secured in a bottom-opening recess of cap 57, so that the latter is freely rotatable coaxially of and relative to the depressible elevator plunger 49 by which it is vertically sustained.

An annular, inverted cup-shaped chip or shaving shield or shroud 59 is force-fitted onto the annular skirt of the plunger cap 57, the skirt of the shroud 59 being of substantial axial length and encircling the top of the fixed tubular column 48 with running clearance. The shroud 59 serves to protect the top plunger and bearing zone of the elevator unit 40 from possible damage by machine shavings or chips, in any vertical position of the plunger.

In order to restrain rotary cap'57 from upward movement relative to the remainder of the plunger structure, a headed stud 60 is provided to extend through a central aperature in cap 57, being threaded downwardly into the top plug 55 of plunger 49. The head 61 of the stud is received in a top counterbore recess of cap 57 for its restraining action, while still permitting rotation of the cap.

The fixed supporting post 43 of unit 40 is provided with a vent passage 62 to atmosphere, through which air may escape from beneath the plunger 49 as the latter is depressed against the opposition of spring 50.

Now referring to FIG. 2 in conjunction with FIG. 3, the upper, work locating and clamping unit 42 also comprises a vertically acting hollow cylindrical plunger 63, closed at its bottom by a generally cylindrical plug 64 secured by bolts 65 to the plunger 63.

As best shown in FIG. 3, a specially and accurately shaped work locator and clamping foot 66 is coaxially suspended from the plunger 63, as by means of a headed stud 67 threaded upwardly into its plug 64, with an enlarged lower head 68 of plug 67 received in a bottom counterbore of locating and clamping foot 66. A ball bearing 69 is coaxially interposed between plug 64 and foot 66, being coaxially piloted on the top of the latter. This bearing permits free rotation of the locating and clamping foot 66, and workpiece P clamped by the latter to the depressible elevator plunger cap 57, since the stud 67 simply sustains the foot 66 while allowing such rotation.

Work locating and clamping foot 66 is provided with a reduced diameter, lower cylindrical locator extension 71 which is accurately proportioned to enter into the center opening 31 of the workpiece or part P. Thus the latter is accurately positioned and piloted coaxially of the units 40, 42, with the part firmly clamped between cap 57 and foot 66 of the respective units. The workpiece P is preliminarily positioned manually for such clamping by resort to an auxiliary side locator gauge structure, which is shown in FIG. 2, being generally designated 72, and which will be hereinafter further described.

Referring now to FIG. 1, the tubular plunger 63 of upper work locating and clamping unit 42 slides in the cylindrical bore of a fixed upright, tubular guide column 74 of unit 42. It may be restrained from rotation in the bore, as by key means corresponding to that of the lower elevator column 48. The column 74 extends downwardly through a center opening 75 in a horizontally extending, rigid bridge part 76 of the superstructure 12 of attachment 10, ,being welded fixedly at the top of such bridge part.

As mounted within the guide column 74, the upper end of the tubular plunger 63 is closed by a fixedly secured top plug 78; and a downwardly extending actuator rod 79 of a double acting air cylinder unit 80 is fixedly threaded into plug 78. Unit 80 is fixedly supported upon a cross piece 81 secured on the top of the column 74. It may be a standard double acting pneumatic unit, operable in reverse directions upon admission of compressed air at opposite ends of its piston (not shown) under the control of the timing valve means 28 shown in FIG. 6.

Thus, as controlled (along with other pneumatic units, as will be described) by the cam set 22 operating the valve units of the valve means 28, the air cylinder 80 causes periodic down and up movements of its plunger 63 and foot 66 to engage and locate the workpiece P, as presented by an attendant from a slide of the machine to the auxiliary side locating or gauge unit 72, then clamp the work part firmly downwardly onto the cap 57 of elevator unit 40. The plunger 49 of the latter is depressed until the workpiece is brought properly down into the plane of radial action of the thread forming rolls 14. Following operation of these rolls (and the facing and chamfering units to be described), the plunger 63 then withdraws upwardly so that the completed workpiece P can be laterally withdrawn from the work area.

The auxiliary work locating unit 72 mentioned above includes (see FIG. 2) a conventional double acting air cylinder 34 bolted onto the top of the superstructure bridge part 76 in laterally spaced relation to the locating and clamping unit 40. This cylinder, as controlled by a two-way valve of valve means 28 (to be described), has the function of controlling the vertical position of an auxiliary side gauge of unit 72 in relation to the workpiece P, prior to operations performed on the latter by the thread rolling and machining devices; so that an operator or attendant may, in a quick movement, position a work blank relatively accurately on the axis of the two units 40, 42, following which the further part locating and working operations take place.

To this end, a piston operated plunger rod 85 of air cylinder 84 extends upwardly from the latter, being connected by a lateral clamp bracket 86 to the upper end of a vertical operating rod 87. The latter extends downwardly through a hole in superstructure part 76; and at its lower end has fixedly secured thereon an arcuate part locator gauge 88 (FIG. 2). This gauge is radially positioned sufficiently outwardly of the stroke of locating and clamping plunger 63 so that a workpiece blank may be thrust against its arcuate surface and thus gauged accurately relative to the axis of the units 40, 42, from which the blank thereafter receives further locating, clamping and guiding support. The timing of the air cylinder 84, through the agency of the cam set or unit 22 and valve means 28 as hereinafter described, is such that the locator gauge 88 is lifted upwardly out of the work zone or area once control of the part is taken over by units 40, .42 and until the forming and machining operations have been completed, the machining units being also retracted. It is returned downwardly, as described above, to assist the attendant in positioning a part.

In the embodiment of the equipment herein shown and described, there are two machining units employed, one being a top surface facing unit or device, generally designated 92 (FIGS. 1 and 2), and the other being an edge chamfering unit or device, generally designated 93. Although but a single machining unit, or more than two, might be employed, the pair will serve for the present descriptive purpose. Units 92, 93 are shown in the illustrated embodiment as being 90 displaced from one another about the rotative axis of work holding units 40, 42 (FIG. 1); and in operative position they act simultaneously on the clamped workpiece, as the latter is rotated under action by thread forming rolls 14, thus to cause unit 92 to form the annular flat, horizontal top face 36 on part P (FIG. 4), and the unit 93 to charnfcr its edge at 37.

Other than in regard to the specific nature of their respective facing and chamfering tool bits 94, 95 (FIG. 2), the units 92, 93 are identical as to mounting and operation; so that in the interest of simplicity, only components associated with the facing unit 92 will be specifically described. This is on the understanding that all corresponding components and parts relating to the chamfering unit 93 are designated by corresponding reference numerals, primed.

For the support of the facing unit 92, the superstructure bridge part 76 (see FIG. 2) is provided with a rigid angle bracket 95 fixedly bolted to the underside thereof. This bracket is integrally or otherwise fixedly secured to the upper one of a pair of parallel guide plates 96; and the latter are in turn rigidly connected to one another by further parallel side plate or strap means 97 (as indicated in FIG. 1) in a mannerto afford a guide housing 98 having an interior space 99 of square or rectangular cross section. Bracket 95 is so contoured that this housing structure is supported at a downward and radially inward angle of about 45 to the vertical, although this will depend, of course, upon the nature of the facing tool 94 and the kind of cut it has to make. A cross strap 100 is rigidly applied across the upper end of the inclined guide housing 98, whose upper end is received in a suitable opening 101 through the superstructure bridge part 76.

The plunger 102 of a double acting air cylinder unit for facer 92, generally designated 103, extends downwardly through an opening in the cross strap 100 into the rectangular guide space 99 of housing 98, in which it is threadedly connected fixedly to a tool slide 104 of square section, which acts reciprocably in the space 99 as guided by housing 98. The facing tool bit 94 is removably clamped in the lower end of the slide by set screws 105; and stop and lock nuts 107 threaded on the plunger 102 are adapted to abut the top guide plate or .strap 100 to adjusta'bly limit the inward operating stroke of tool slide 104 and bit 94.

The air cylinder unit 103 for facing tool device or unit 92 is rigidly supported above the superstructure part 76 by means of a fixed angle bracket 108 atop the latter,

bracket 108 having an inclined flange 109 to which a 9 double acting air cylinder 110 is fixedly mounted. The internal piston (not shown) of this pneumatic cylinder is connected to the plunger rod 102, the latter extending through the superstructure opening 101. time the stroke unit 92 at its stroke ends, the connecting rod 112 of a suitable standard hydraulic brake 113 is adjustably connected to cylinder plunger rod 102, as by means of a lateral bracketarm 114 and lock nuts 115 adjustably threaded on the plunger rod. Brake 112 is appropriately supported on superstructure bracket 1118 adjacent the air cylinder 11%.

As shown in FIG. 2, the double acting, facing tool actuating air cylinder 110 has air pressure intake conduits or lines 117, 118 communicating with its opposite ends;

and these pressure lines are illustrated in FIGS. and 6 as in turn communicating with the housing 120 of a timing control valve unit, generally designated 121, for the facing device 92. Housing 120 has its support on the fixed auxiliary or adapter plate member 26 of the superstructure 12 on the thread rolling machine, or it may be correspondingly supported fixedly by any part of the machine proper. p

The valve 121 is one of a number of valve units of the valve set 28, and is an entirely conventional, sliding barrel type equipped with an air pressure intake conduit or fitting 122 which communicates the same with a suitable source (not shown) of air under pressure. Pursuant to the usual operation of such a valve unit, its internal valve member (not shown) is shifted in one direction or the other to communicate the pressure applied to the valve through conduit 122 to one or the other of the pressure lines 117, 118, and to one end or the other of the air cylinder 110 which controls radial in and out reversing movement of the facing tool slide 104 in its inclined path.

The operation of the internal valve barrel referred to above is controlled by a plunger rod 124 axially connected thereto and projecting outwardly of valve 121 in a direction radial of the timing cam set or unit 22, as shown in FIGS. 5 and 6; and plunger rod 124 has a clevis end equipped with an anti-friction roller 125 which follows the face of a timing control earn 127 of the set 22 governing face machining unit or device 92. As shown in FIGS. 5 and 6, this cam is a dual-plate one, including superimposed, individually shaped cam plates 128, 129 adjustably secured to one another by means of a lock screw 130 on one thereof received in an arcuate slot 131 in the other. Thus, upon appropriate adjustment the timing cam 127 may be made to present a low 132 of adjustably variable circumferential extent, merging at its opposite ends with a remaining circular high 133 of the composite cam.

FIGS. 5 and 6 are quite schematic in nature, FIG. 6 showing the valve units 121, 121' for the respective facing and chamfering units 92, 93 as being directly superimposed on one another, with their corresponding control cams 127, 127' correspondingly oriented for simultaneous movements of the facing and chamfering units 92, 93.

Valve 121' will be provided with pressure intake and dualdischarge lines corresponding to the lines 122, 117, 118, and correspondingly connected to opposite ends of the cylinder (not shown) controlling chamfering unit 93; and it is to be kept in mind that all parts for unit or device 93 (FIGS. 1 and 2) are structurally the same as those for the'facing unit 92, hence bearing the same corresponding reference numerals, primed.

The composite cams 127, 127 are adjustably secured, as by split clamp collars 135, 135' thereon, to an upright shaft 136, which is in eifect an axial top extension of the motor-driven shaft on which the master cam 18 of the thread rolling machine is driven; and a top lock nut 137 on shaft 136 locks all cams of the set or unit 22 for rotation in synchronism with main cam 18.

In order to The air cylinder (Fig. 2) which actuates the plunger 63 of the part locating and clamping unit 42 for its up and down movements is operated by a valve of the valve set 28 which is the same as the control valves 121, 121 for facing and chamfering devices 92, 93, although spaced angularly on support 26 from those valves about the axis of unit 42. Since the cylinder 80 has pneumatic control connections which are the same as the facing control cylinder 110, its corresponding parts are designated by corresponding reference numerals, double-primed (see FIGS. 2 and 5) and further description is dispensed with. As shown in FIG. 6, the valve unit 121 for cylinder 89 is controlled by a top plate cam 138 of the cam set 22.

Further included in said cam set 22 is a fourth rotary plate cam 140 controlling the action of a two-way valve 141 (FIG. 5), which is also mounted on the machine or superstructure support 26. Valve 141 has an anti-friction control arm 142 which follows earn 140 to control the timed action of the small upright air cylinder 84 (FIG. 2),th11s governing the vertical position of the auxiliary side locator gauge 88 in the manner described above.

It is seen that attachment equipment 10 of the invention is readily applicable to a standard thread forming machine Without extensive modification of the latter, and which operates after installation in an accurately timed synchronism with the action of the machine, deriving its basic pneumatic control of the facing and chamfering units 92, 93 from a cam set 22 which becomes, in efiect a part of the cam control of the thread rolling machine, as converted by the equipment to combine the rolling, facing and chamfering operations. In connection with the production of a part such as the part P, it has'been the practice to face and chamfer the piece independently of the rolling of its thread, but it has been found impossible thus to attain the accurate relationship of threaded and machined surfaces necessary for the particular workpiece in question. By combining the chamfering and facing operations with the thread rolling operation, commencing then after the set of threading rolls 14 have had a good grip on part P, the faced and chamfered work surfaces 36 and 37 are formed with the desired and needed precision.

What I claim as my invention is:

1. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a thread forming roll movable into and out of thread-rolling engagement with the latter, and operating means to so move said roll; said equipment comprising mounting means fixedly applicable to said machine, a machining head mounted by said mounting means for movement in a path into and out of material removing engagement with said workpiece, a device on eratively connected to said machining head to so move the latter reversibly in said path, control means operatively connected to said device to control the movement of the latter, and means operatively connecting said control means to said operating means of said machine for operation of said control means in timed relation to said movement of said thread forming roll, said last named means including means driven in said timed relation and operating said control means to cause said device to engage said machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece.

2. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a rotatively driven thread forming roll movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll; said equipment comprising mounting means fixedly applicable to said machine in vertically spaced relation to said roll, means mounted by said mounting means to move into and out of engagement with the workpiece and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said roll, a machining head mounted by said mounting means for movement in a radially inwardly inclined path relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressureoperated device mounted on said mounting means and operatively connected to said machining head to so move the latter reversibly in said path, control valve means operatively connected to said device to control the movement of the latter, and means operatively connecting said control valve means to said operating means of said machine for operation of said control valve means in timed relation to the radial movement of said thread forming roll, said last named means including cam means driven in said timed relation and operating said control valve means to cause said fluid pressure operated device to engage said machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece.

3. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a rotatively driven thread forming roll movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll; said equipment comprising mounting means fixedly applicable to said machine in vertically spaced relation to said roll, means mounted by said mounting means to move into and out of engagement with the workpiece and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said roll, a machining head mounted by said mounting means for movement in a radially inwardly inclined path relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressure-operated device mounted on said mounting means and operatively connected to said machining head to so move the latter reversibly in said path, control valve means operatively connected to said device to control the movement of the latter, and means operatively connecting said control valve means to said operating means of said machine for operation of said control valve means in timed relation to the radial movement of said thread forming roll, said last named means including cam means driven in said timed relation and operating said control valve means to cause said fluid pressure-operated device to engage said machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece, said radial path of said machining head being angularly spaced about said axis of rotation of the workpiece from the radial path of said thread forming roll, said workpiece being engaged by said head in spaced relation to its engagement by said thread forming roll.

4. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a rotatively driven thread forming roll movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll; said equipment comprising mounting means fixedly applicable to said machine in vertically spaced relation to said roll, means mounted by said mounting means to move into and out of engagement with the workpiece and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said roll, a fluid-pressure operated device to so move said guide means, a machining head mounted by said mounting means for movement in a radially inwardly inclined path relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressure-operated device mounted on said mounting means and operatively connected to said machining head to so move the latter reversibly in said path, control valve means operatively connected to said devices to control movements of the latter, and means operatively connecting said control valve means to said operating means of said machine for operation of said control valve means in timed relation to the radial movement of said thread forming roll, said last named means including cam means driven in said timed relation and operating said control valve means to cause said fluid pressure-operated devices to engage said guide means and machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece.

5. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a rotatively driven thread forming roll movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll; said equipment comprising mounting means fixedly applicable to said machine in vertically spaced relation to said roll, means mounted by said mounting means to move into and out of engagement with the workpiece and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said roll, a fluid pressure-operated device to so move said guide means, a machining head mounted by said mounting means for movement in a radially inwardly inclined path relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressure-operated device mounted on said mounting means and operatively connected to said machining head to so move the latter reversibly in said path, control valve means operatively connected to said devices to control the movements of the latter, and means operatively connecting said control valve means to said operating means of said machine for operation of said control valve means in timed relation to the radial movement of said thread forming roll, said last named means including cam means driven in said timed relation and operating said control valve means to cause said fluid pressureoperated devices to engage said guide means and machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece, said radial path of said machining head being angularly spaced about said axis of rotation of the workpiece from the radial path of said thread forming roll, said .workpiece being engaged by said head in spaced relation to its engagement by said thread forming roll.

6. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a rotatively driven thread forming roll movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll; said equipment comprising mounting means fixedly applicable to said machine in vertically spaced relation to said roll, means mounted by said mounting means to move into and out of engagement with the workpiece and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said roll, a fluid pressure-operated device to so move said guide means, a machining head mounted by said mounting means for movement in a radially inwardly inclined path relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressure-operated device mounted on said mounting means and operatively connected to said machining head to so move the latter reversibly in said path, control valve means operatively connected to said devices to con trol the movements of the latter, a workpiece locating gauge mounted for movement into and out of position for engagement by the workpiece to locate the latter accurately in position on said rotative axis to be operated on by said roll and machining head, means to so move said gauge, and means operatively connecting said control valve means to said operating means of said machine for operation of said control valve means in timed relation to the radial movement of said thread forming roll, said last named means including cam means driven in said timed relation and operating said control valve means to cause said fluid pressure-operated devices to engage said guide means and machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece, said radial path of said machining head being angularly spaced about said axis of rotation of the workpiece from the radial path of said thread forming roll, said workpiece being engaged by said head in spaced relation to its engagement by said thread forming roll.

'7. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being of the type having a rotatively driven thread forming roll movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll; said equipment comprising mounting means fixedly applicable to said machine in vertically spaced relation to said roll, means mounted by said mounting means to move into and out of engagement with the workpiece and guide the workpiece for rotation on said axis, as the workpiece is rolling-1y engaged by said roll, a fluid pressure-operated device to so move said guide. means, a machining head mounted by said mounting means for movement in a radially inwardly inclined path relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressure-operated device mounted on said mounting means and operatively connected to said machining head to so move the latter reversibly in said path, control valve means operatively connected to said devices to con trol the movements of the latter, a workpiece locating gauge mounted for movement into and outof position for engagement by the workpiece to locate the latter accurately in position on said rotative axis to be operated on by said roll and machining head, fluid pressure-operated means to so move said gauge, means opera-ting said last named means in timed relation to said devices, and means operatively connecting said control valve means to said operating means of said machine for operation of said control valve means in timed relation to the radial movement of said thread forming roll, said last named means including cam means driven in said timed relation and operating said control valve means to cause said fluid pressure-operated devices to engage said guide means and machining head with said workpiece after said thread forming roll has had thread forming engagement with the workpiece, said radial path of said machining head being angularly spaced about said axis of rotation of the workpiece from the radial path of said thread forming roll, said workpiece being engaged by said head in spaced relation to its engagement by said threadforming roll.

8. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being characterized by a rotatively driven set of thread forming rolls movable radially in coplanar horizontal paths relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and

operation of said units and devices in timed relation to operating means to so move and rotatively drive said roll set, said equipment comprising a superstructure having means to mount the same on said machine above said rolls, means mounted by a part of said superstructure to move into and out of engagement with the workpiece from above and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said rolls, a fluid pressure-operated device to so move said guide means, a set of angularly spaced machining heads mounted by a part of said superstructure for movement in individual, downwardly and radially inwardly inclined paths relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including fluid pressureoperated devices mounted on a part of said superstructure and operatively connected respectively to said machining heads to so move the latter reversibly in their respective paths, valve units operatively connected respectively to said devices of said guide means and heads to control their movements, and means operatively connecting said valve units to said operating means of said machine for operation of said units and devices in timed relation to the radial movements of said thread forming rolls, said last named means including cam means having means to drivingly connect the same to said machine to be driven in said timed relation, said cam means operating said valve units to cause said fluid pressure-operated devices to engage said guide means and machining heads with said workpiece after said thread forming roll set has had thread forming engagement with the workpiece.

9. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being characterized by .a rotatively driven set of thread forming rolls movable radially in coplanar horizontal paths relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll set, said equipment comprising a superstructure having means to mount the same on said machine above said rolls, means mounted by a part of said superstructure to move into and out of engagement with the workpiece from above and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said rolls, a fluid pressure-operated device to so move said guide means, a set of angularly spaced machining heads mounted by a part of said superstructure for movement in individual, downwardly and radially inwardly inclined paths relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including fluid pressure-operated devices mounted on a part of said superstructure and operatively connected respectively to said machining heads to so move the latter reversibly in their respective paths, valve units operatively connected respectively to said devices of said guide means and heads to control their movements, and means operatively connecting said valve units to said operating means of said machine for the radial movements of said thread forming rolls, said last named means including cam means having means to drivingly connect the same to said machine to be driven in said timed relation, said cam means operating said valve units to cause said fluid pressure-operated devices to engage said guide means and machining heads with said workpiece after said thread forming roll set has had thread forming engagement with the workpiece, said radial paths of said machining heads being angularly spaced about said axis of rotation of the workpiece from the respective radial paths of said thread forming rolls, said workpiece being engaged by said heads in vertically spaced relation to its engagement by said thread forming roll set.

10. The combination with a thread rolling machine of equipment to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine having a rotatively driven set of thread forming rolls movable radially in coplanar horizontal paths relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll set, said equipment comprising a superstructure fixedly mounted on said machine above said rolls, means mounted by a part of said superstructure to move into and out of engagement with the workpiece from above and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said rolls, a fluid pressure-operated device to so move said guide means, a set of angularly spaced machining heads mounted by a part of said superstructure for movement in individual, downwardly and radially inwardly inclined paths relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including fluid pressure-operated devices mounted on a part of said superstructure and operatively connected respectively to said machining heads to so move the latter reversibly in their respective paths, valve units operatively connected respectively to said devices of said guide means and heads to control their movements, and means operatively connecting said valve units to said operating means of said machine for operation of said units and devices in timed relation to the radial movements of said thread forming rolls, said last named means including cam means having means to drivingly connect the same to said machine to be driven in said timed relation, said cam means operating said valve units to cause said fluid pressure-operated devices to engage said guide means and machining heads with said workpiece after said thread forming roll set has had thread forming engagement with the workpiece.

11. The combination with a thread rolling machine of equipment to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine having a rotatively driven set of thread forming rolls movable radially in coplanar horizontal paths relative to the rotative axis of the workpiece and into and out of thread-rolling engagement With the latter, and operating means to so move and rotatively drive said roll set, said equipment comprising a superstructure fixedly mounted on said machine above said rolls, means mounted by a part of said superstructure to move into and out of engagement with the workpiece from above and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said rolls, a fluid pressure-operated device to so move said guide means,

a set of angularly spaced machining heads mounted by a pant of said superstructure for movement in individual, downwardly and radially inwardly inclined paths relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including fluid pressure-operated devices mounted on a part of said superstructure and operatively connected respectively to said machining heads to so move the latter reversibly in their respective paths, valve units operatively connected respectively to said devices of said guide means and heads to control their movements, and means operatively connecting said valve units to said operating means of said machine for operation of said units and devices in timed relation to the radial movements of said thread forming rolls, said last named means including cam means having means to drivingly connect the same to said machine to be driven in said timed relation, said cam means operating said valve units to cause said fluid pressure-operated devices to engage said guide means and machining heads with said workpiece after said thread forming roll set has had thread forming engagement with the workpiece, said radial paths of said machining heads being angularly spaced about said axis of rotation of the workpiece from 16 the respective radial paths of said thread forming rolls, said workpiece being engaged by said heads in vertically spaced relation to its engagement by said thread forming roll.

12. Equipment for use with a thread rolling machine to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine being characterized =by a rotatively driven set of thread forming rolls movable radially in coplanar horizontal paths relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll set, said equipment comprising a superstructure having means to mount the same on said machine above said rolls, means mounted by a part of said superstructure to move into and out of engagement with the workpiece from above and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said rolls, a fluid pressure-operated device to so move said guide means, a set of angularly spaced machining heads mounted by a part of said superstructure for movement in individual, downwardly and radially inwardly inclined paths relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including fluid pressure-operated devices mounted on a part of said superstructure and operatively connected respectively to said machining heads to so move the latter reversibly in their respective paths, a workpiece locating gauge mounted for movement into and out of position for engagement by the workpiece to locate the latter accurately in position on said rotative axis to be operated on by said rolls and machining heads, fluid pressure-operated means to so move said gauge, means operating said last named means in timed relation to said devices, valve units operatively connected respectively to said devices of said guide means and heads to control their movements, and means operatively connecting said valve units to said operating means of said machine for operation of said units and devices in timed relation to the radial movements of said thread forming rolls, said last named means including cam means having means to drivingly connect the same to said machine to be driven in said timed relation, said cam means operating said valve units to cause said fluid pressure-operated devices to engage said guide means and machining heads with said workpiece after said thread forming roll set has had thread forming engagement with the workpiece.

13. The combination with a thread rolling machine of equipment to turn a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine having a rotatively driven set of thread forming rolls movable radially in coplanar horizontal paths relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move and rotatively drive said roll set, said equipment comprising a superstructure fixedly mounted on said machine above said rolls, means mounted by a part of said superstructure to move into and out of engagement with the workpiece from above and guide the workpiece for rotation on said axis, as the workpiece is rollingly engaged by said rolls, a fluid pressureoperated device to so move said guide means, a set of angularly spaced machining heads mounted by a part of said superstructure for movement in individual, downwardly and radially inwardly inclined paths relative to the rotating workpiece and its rotative axis and into and out of material removing engagement with said workpiece, means including fluid pressure-operated devices mounted on a part of said superstructure and operatively connected respectively to said machining heads to so move the latter reversibly in their respective paths, a workpiece locating gauge mounted for movement into nd out of position for engagement b the workpiece to locate the latter accurately in position on said rotative axis to be operated on "by said rolls and machining heads, fluid pressure-operated means to so move said gauge, means operating said last named means in timed relation to said devices, valve units operatively connected respectively to said devices of said guide means and heads to control their movements, and means operatively connecting said valve units to said operating means of said machine for operation of said units and devices in timed relation to the radial movements of said thread forming rolls, said last named means including cam means having means to drivingly connect the same to said machine to be driven in said timed relation, said cam means operating said valve units to cause said fluid pressureoperated devices to engage said guide means and machining heads with said workpiece after said thread forming roll set has had thread forming engagement with the workpiece.

14. Equipment for use with a thread rolling machine to turn a surface of 'a rotating workpiece coordinately with the rolling of a thread on the latter by said machine, said machine having a set of thread forming rolls movable radially relative to the rotative axis of the workpiece and into and out of thread-rolling engagement with the latter, and operating means to so move said roll set; said equipment comprising a superstructure having means to mount the same on said machine above said rolls, a machining head mounted by a part of said superstructure for movement in a downwardly and radially inwardly inclined path relative to said rotative axis and into and out of material removing engagement with said workpiece, means including a fluid pressure-operated device mounted on said thread rolling machine and operatively connected to said machining head to so move the latter reversibly in said path, valve means operatively connected to said devices to control the reversing movements of the latter, and means operatively connecting said valve means to said operating means of said machine for operation of said valve means in timed relation to the radial movements of said thread forming rolls, said last named means including cam means having means to connect the same to said machine to be driven in said timed relation, said cam means operating said valve means to cause the latter and said fluid, pressure operated devices to engage said machining head with'said workpiece after said thread forming roll set has had thread forming engagement with the workpiece.

15. Equipment in accordance with claim 14, and further comprising means to locate and guide said workpiece for rotation on said axis while being operated on by said roll set and machining head, said clamp and guide means comprising an elevator unit having .an upwardly springbiased'plunger coaxial with said axis, and a workpiece supporting cap rotatably mounted on the top of said plunger by an anti-friction bearing, said cap having an annular shroud fixed thereon and depending beneath the same to externally shield the zone of said bearing.

16. Equipment in accordance with claim 14, and further comprising means to locate and guide said workpiece for rotation on said axis while being operated on by said roll set and machining head, said clamp and guide means comprising an elevator unit having an upwardly springbiased plunger coaxial with said axis, and a workpiece supporting cap rotatably mounted on the top of said plunger by an anti-friction bearing; and a workpiece locating and clamping unit mounted on said superstructure coaxi-ally above said elevator unit, said last named unit comprising a locating and clamping plunger movable into engagement with the workpiece from above to de press the latter, as rotatably supported by said cap of said elevator unit, to the level of said roll set for rolling by said set.

17. Equipment in accordance with claim 14, and furthe-r comprising means to locate and guide said workpiece for rotation on said axis while being operated on by said roll set and machining head, said clamp and guide means comprising an elevator unit having an upwardly springbiased plunger coaxial with said axis, and a workpiece supporting cap rotatably mounted on the top of said plunger by an anti-friction bearing, said cap having an annular shroud fixed thereon and depending beneath the same to externally shield the zone of said bearing; and a workpiece locating and clamping unit mounted on said superstructure coaxially above said elevator unit, said last named unit comprising a locating and clam-ping plunges" movable into engagement with the workpiece from above to depress the latter, as rotatably supported by said cap .of said elevator unit, to the level of said roll set for rolling by said set, a fluid pressureoperated device to so move said locating and clamping plunger, and valve means controlling movement of the last named plunger to engage the workpiece in timed relation to radial movements of said roll set and machining head relative to the work-piece.

18. Equipment in accordance with claim 14, and further comprising means to locate and guide said workpiece for rotation on said axis while being operated on by said roll set and machining head, said clamp and guide means comprising an elevator unit having an upwardly spring-biased plunger coaxial with said axis, and a workpice supporting cap rotatably mounted on the top of said plunger by an anti-friction bearing; and a workpiece locating and clamping unit mounted on said superstruct-ure coaxia lly above said elevator unit, said last named unit comprising a locating and clamping plunger movable into engagement with the workpiece from above to depress the latter, as rotatably supported by said cap of said elevator unit, to the level of said roll set for rolling by said set, a fluid pressure-operated device to so move said locating and clamping plunger, and valve means control-ling movement of the last named plunger to engage the workpiece in timed relation to radial movements of said roll set and machining head relative to the workpiece. i

19. Equipment in accordance with claim 14, and further comp-rising means to locate and guide said workpiece for rotation on said axis While being operated on by said roll set and machining head, said clamp and guide means comprising an elevator unit having an upwardly springbiased plunger coaxial with said axis, and a workpiece supporting cap rotatably mounted on the top of said plunger by an anti-friction bearing; and a workpiece locating and clamping unit mounted on said superstructure coaxiallly above said elevator unit, said last named unit comprising a locating and clamping plunger movable into engagement with the workpiece from above to depress the latter, as rotatably supported by said cap of said elevator unit, to the level of said roll set for rolling by said set, a fluid pressure-operated device to so move said locating and clamping plunger, and valve means controlling movement of the last named plunger to engage the workpiece in timed relation to radial movements of said roll set and machining head relative to the workpiece, said last named valve means being operated by said cam means.

20. Equipment in accordance with claim 14, and further comprising means to locate and guide said workpiece for rotation on said axis while being operated on by said roll set and machining head, said clamp and guide means comprising an elevator unit having an upwardly springbias-ed plunger coaxial with said axis, and a workpiece supporting cap rotatably mounted on the top of said plunger by an anti-friction bearing; said cap having an annular shroud fixed thereon and depending beneath the same to externally shield the zone of said bearing; and a workpiece locating and clamping unit mounted on said superstructure coaxially above said elevator unit, said last named unit comprising a locating and clamping plunger movable into engagement with the workpiece from above to depress the latter, as rotatably supported by said cap of said elevator unit, to the level of said roll set for rolling by said set, a fluid pressure-operated device to so move said locating and clamping plunger and valve means controlling movement of the last named plunger to engage the workpiece in timed relation to radial movements of said roll set and machining head relative to the workpiece, said last named valve means being operated by said cam means.

References Cited by the Examiner UNITED STATES PATENTS 2,352,185 6/ 1944 Bulla-rd et al 29-29 2,643,402 6/1953 Bil'low 104 3,011,245 12/1961 Mueller 29-38.l

CHARLES W. LANHAM, Primary Examiner.

10 H. D. HOINKES, Assistant Examiner. 

1. EQUIPMENT FOR USE WITH A THREAD ROLLING MACHINE TO TURN A ROTATING WORKPIECE COORDINATELY WITH THE ROLLING OF A THREAD ON THE LATTER BY SAID MACHINE, SAID MACHINE BEING OF THE TYPE HAVING A THREAD FORMING ROLL MOVABLE INTO AND OUT OF THREAD-ROLLING ENGAGEMENT WITH THE LATTER, AND OPERATING MEANS TO SO MOVE SAID ROLL; SAID EQUIPMENT COMPRISING MOUNTING MEANS FIXEDLY APPLICABLE TO SAID MACHINE, A MACHINING HEAD MOUNTED BY SAID MOUNTING MEANS FOR MOVEMENT IN A PATH INTO AND OUT OF MATERIAL REMOVING ENGAGEMENT WITH SAID WORKPIECE, A DEVICE OPERATIVELY CONNECTED TO SAID MACHINING HEAD TO SO MOVE THE LATTER REVERSIBLY IN SAID PATH, CONTROL MEANS OPERATIVELY CONNECTED TO SAID DEVICE TO CONTROL THE MOVEMENT OF THE LATTER, AND MEANS OPERATIVELY CONNECTING SAID CONTROL MEANS TO SAID OPERATING MEANS OF SAID MACHINE FOR OPERATION OF SAID CONTROL MEANS OF SAID MACHINE FOR MOVEMENT OF SAID THREAD FORMING ROLL, SAID LAST NAMED MEANS INCLUDING MEANS DRIVEN IN SAID TIMED RELATION AND OPERATING SAID CONTROL MEANS TO CAUSE SAID DEVICE TO ENGAGE SAID MACHINING HEAD WITH SAID WORKPIECE AFTER SAID THREAD FORMING ROLL HAS HAD THREAD FORMING ENGAGEMENT WITH THE WORKPIECE. 